Voltage regulators are frequently used for providing a load current at a stable load voltage to different types of loads (e.g. to the processors of an electronic device). A voltage regulator derives the load current from an input node of the regulator, while regulating the output voltage at the output node of the regulator in accordance to a reference voltage.
Linear regulators may also be referred to as three-terminal regulators. The three main terminals of a linear regulator may be described as (1) input terminal, which is connected to an unregulated input voltage source, (2) output terminal, which provides a regulated output voltage source, and (3) ground. The control circuitry of a linear regulator (also referred to herein as differential amplification unit), which typically includes feedback, compensation and voltage regulation, may comprise one or more amplifiers, a Miller capacitor, a current source. The control circuitry defines the operating conditions and system performance of the linear regulator. The dynamic load performance, the loop stability, and the no-load/light-load internal power consumption (given by the quiescent current IQ times the input voltage) are examples of operating parameters that are dependent on the setting and/or design of the control circuitry.
A linear regulator is typically used in conjunction with an output capacitor which is external to the linear regulator device and which is typically selected by a system designer for the application that the linear regulator is used for. The fixed control circuitry of a linear regulator is typically designed to suit different output capacitors. However, the performance of a linear regulator (notably the power consumption of a linear regulator) is typically not optimal for the different output capacitors.